Btrfs: many file_write fixes, inline data

Signed-off-by: Chris Mason <chris.mason@oracle.com>

1 files changed, 6 insertions, 0 deletions

diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index a2a3f529cad..11e17a2f736 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -108,6 +108,12 @@ int btrfs_map_bh_to_logical(struct btrfs_root *root, struct buffer_head *bh,
 
         int ret;
 
+        if (logical == 0) {
+                bh->b_bdev = NULL;
+                bh->b_blocknr = 0;
+                set_buffer_mapped(bh);
+                return 0;
+        }
         root = root->fs_info->dev_root;
         ret = radix_tree_gang_lookup(&root->fs_info->dev_radix,
                                      (void **)lookup,